Existing hall call allocation systems attempt to find an optimum solution for assigning new hall calls to a group of elevator cars. Typically, the existing systems and methods use neural networks, genetic algorithms, and/or fuzzy logic to optimize hall call allocations based on criteria such as waiting time, time to destination, and elevator usage. These systems typically try to minimize waiting times. Some of the newer systems try to minimize average journey time. Journey time is the time from the entry of a hall call (or joining the queue if a previous passenger has entered a hall call) to arrival at the destination.
Several energy minimization systems have been proposed. U.S. Pat. No. 4,402,387 evaluates three elevator velocities and selects the one that uses the least amount of energy. U.S. Pat. Nos. 3,891,064 and 6,199,667 have the ability to select one of three velocity profiles depending on whether the goals are energy use or traffic handling. All of these patents make decisions about the elevator car's next trip. None of these three patents address a total dispatching system of energy minimization.
In view of the above, there is a need for a system that minimizes the total use of energy in lieu of minimizing waiting time or journey time when energy use is more important than traffic handling.